RE: CCTV camera on TV

["Stephen Jones" <ukha@xxxxxxxxxxxx>]

Thanks=20

That may have been the problem, although I don't have the PC here any more
to try out the fix. I've just tried turning the video overlay off on my
current PC and couldn't find where this is done, if possible. Maybe you
can't turn it off with certain cards? (Mine has a NVidia GeForce4 MX4000)

I think I'd rather use the DSP8 where possible, especially as the price
should be dropping. I can't get Roy of RF to commit to how much on any of
the GV stuff, but if the DSP8 came down towards the =A3100 mark it'd make
t=
he
cost difference between modulators & switcher a lot less.

Steve

-----Original Message-----
From: Paul Gale [mailto:groups@xxxxxxx]=20
Sent: 31 December 2004 10:44
To: ukha_d@xxxxxxx
Subject: RE: [ukha_d] CCTV camera on TV

That's correct Gordon,

You may be able to get what you want though by disabling the overlay
surfac=
e
and forcing the graphics card display drivers to render the video surface
i=
n
software. Matrox cards have this facility in the Powerdesk app (use video
overlay - disabled). I've used this to capture video windows where they
would normally be a black (or purple) screens.

There may be a slight degradation in performance and/or video window
qualit=
y
by disabling the video overlay although I can't say as I notice it.

Other cards/drivers may or may not allow you to do the same.

Paul.

> -----Original Message-----
> From: Paul Gordon [mailto:paul@xxxxxxx]
> Sent: 31 December 2004 10:17
> To: ukha_d@xxxxxxx
> Subject: RE: [ukha_d] CCTV camera on TV
>=20
> I have seen something like this before, and IIRC it was something to
do
> with the "video overlay" mode... If I have understood the
concept of
> what was going on correctly, (and it's *extremely* likely that I
> haven't!), I think the problem was something along the lines of the PC
> graphics card is not responsible for rendering the video part of the
> display, but instead just leaves a blank "hole" in the
screen where
> another bit of hardware or software then "fills in" the gap
with the
> video...
>=20
> I saw this result in an annoying feature of my Matrox G400 dual-head
> graphics card that only (as I now know) supports video overlay on one
of
> the two displays. This meant that when I tried to play DVD's, media
> player would come up; I'd get the sound, but no video... It took me
ages
> to figure out what was going on, since I thought I had the wrong
codec's
> installed or something, and since the two displays were in different
> locations (and couldn't both be seen at once), it took me a while to
> realise that the video displayed OK on the other monitor.... swapped
the
> VGA plugs around, and viola, I had the DVD video on the display where
I
> wanted it...
>=20
> This sounds like it could be your problem, and since the graphics card
> isn't rendering the video part of the display, I guess there's no way
> you'll ever capture it by doing a screen grab, which I guess just
grabs
> the data stream from the graphics card...=20